1. Field of the Invention
The present invention relates generally to methods and devices for surgically treating obese individuals. More particularly, the present invention relates to a method and device for performing gastroplasty procedures relying on the laparoscopic placement and stapling of a vertical band partitioning the individual's stomach.
Obesity is the most frequent nutritional disorder in Western civilization. In the U.S., over 34 million citizens between the ages of 20-75 are overweight, and of those, 12.4 million are morbidly obese, i.e. being 100 pounds over their desirable weight or having one or more serious medical conditions in association with obesity. Such morbid obesity carries with it a greatly enhanced risk of premature death, particularly between the ages of 25-35, where there is a 12-fold increased risk of death compared with the non-obese. The most common causes of death are heart disease, stroke, diabetes mellitus, cancer, pulmonary diseases, and accidents.
Presently there are but two methods of treatment for morbid obesity--diet and surgery. Numerous studies have found diet alone is generally unsuccessful with recidivism rates approaching 95%. After abandoning the highly successful jejunal-ileal bypass surgical procedure performed in the early 70's because of its unacceptably high rate of late metabolic complications, surgeons have developed two different gastric surgical approaches--the Vertical Banded Gastroplasty (hereafter called VBG) and the Gastric Bypass. Each of these procedures has its advantages and disadvantages. The Gastric Bypass, which entails short circuiting the gastric pouch, has previously been more successful in bringing about sustained weight loss. However, the procedure is more difficult to perform, has a higher rate of catastrophic post-operative complications, and produces long term deleterious changes due to the rerouting of the alimentary flow.
Vertical Banded Gastroplasty is more commonly performed than Gastric Bypass because it is simpler, has fewer major complications, and does not disturb normal alimentary continuity. VBG relies on stapling the stomach to create a small partitioned pouch high up in the stomach that can contain no more than 50 ml of food and liquid, where the pouch has a small diameter (typically not exceeding 10.7 mm) controlled non-dilatable outlet to the larger stomach. The smaller pouch which receives food and liquid directly from the esophagus (gullet) will fill quickly. Because the outlet from this smaller pouch into the larger stomach is quite narrow, the patient will experience early satiety, which in turn will decrease the appetite and result in weight loss.
Vertical Banded Gastroplasty is accomplished by accessing the patient's general peritoneal cavity through a very long abdominal incision and an exemplary procedure involves the following steps.
Step 1: The lesser curvature of the stomach is dissected from any attaching structures over a distance of about 3 or 4 cm. This requires clearing all blood vessels and nerves from the anterior and posterior aspects of the stomach.
Step 2: A 32 French Ewald rubber tube is placed through the patient's mouth and into the stomach and is held against the lesser curvature (32f=10.7 mm, this tube calibrates the size of the outlet). A special stapling device called an EEA.TM. (U.S. Surgical Corporation, Norwalk, Connecticut) punctures both gastric walls, then punches-out and seals a 28 mm diameter circle in both walls of the stomach. Thus, a small hole is created in the stomach by stapling the front and back walls of the stomach together.
Step 3: A second stapling device (TA-90B.TM., available from U.S. Surgical Corporation, Norwalk, Connecticut) is specially designed to place 4 rows of linear staples and is introduced through the stomach hole so that the lower jaw of the staple device is on the back wall of the stomach and the upper jaw of the staple device is on the front wall of the stomach. The length of stomach that needs to be stapled varies from 5-9 cm. The TA-90B.TM. stapling device is then placed so that its longitudinal axis is parallel to a line from the opening of the esophagus to the new outlet opening constructed next to the punched-out hole. After measuring the proposed volume of the partitioned pouch and making it somewhere between 15 ml and 50 ml, staples in a double row are then fired through both walls of the stomach.
The stomach is now compartmentalized into a smaller proximal pouch which can accommodate only small portions of food. To gain access to the much larger portion of the stomach and the remainder of the digestive tract, food must pass through the narrow exit opening which is the new outlet from the smaller proximal portion of the stomach.
Step 4: The new outlet is encircled with a band of polypropylene non-absorbable mesh which measures 5.5 cm.times.1.5 cm (the mesh resembles a screen door). This band encircling the newly constructed outlet will form a collar. The mesh is placed through the punched-out hole and is secured around the outer surface of the outlet. The mesh, once sutured to itself, prevents the inner diameter of the outlet of the stomach from stretching beyond is initial diameter.
Thus, the steps of the VBG procedure compartmentalize the stomach into a larger portion and a smaller portion. The smaller portion is vertically stapled and its outlet banded with a piece of non-absorbable mesh to insure that it will not increase in size. The smaller pouch will hold a volume of 15-50 ml, and the exit opening, by virtue of its being banded, will not increase in diameter. Such features serve to insure that the patient who attempts to eat too much, too fast will have early satiety and not overeat.
While this procedure has been successful, it suffers from the fact that obese patients are poor surgical risks. The surgery requires a very long incision, extending through an extremely thick layer of fat. Post-operative healing of such incisions is highly problematic. The procedure is difficult for the surgeon to perform because of the poor exposure associated with the enormous size of these patients.
With the exception of a few centers, VBG has fallen into disuse because of the difficulties associated with the performance of the procedure and the high rate of complications that ensue afterwards. Early complications, such as wound infection, pulmonary emboli, gastric perforation, and subphrenic abscess, are serious and the early mortality figure in the best series runs between 1-3%. Many early complications necessitate reoperation.
Late compilations, such as ventral (incisional) hernias and gallbladder stones, also occur. The most troubling late complication is a disruption of the vertical linear rows of staples. When this occurs, the smaller partitioned stomach now has two openings into the larger stomach and the benefits of the procedure are immediately negated.
In recent years, less invasive surgical (LIS) techniques, such as laparoscopic, thoracoscopic, and arthroscopic techniques, have been performed through small incisions. Such LIS procedures use specialized instruments to carry out the desired surgical result. For abdominal surgery, the specialized instruments are usually introduced through a tube, such as a trocar, while the surgeon observes the manipulation of the instruments through a laparoscope. The image is transmitted by means of a camera attached to the laparoscope to a visual monitor. LIS techniques offer significant advantages over conventional "open" surgical procedures. In particular, the LIS techniques are generally much less traumatic, require substantially shorter recovery periods, and are less costly than corresponding, conventional surgical techniques such as open abdominal surgery.
Accordingly, it would be desirable to provide methods and devices for laparoscopically performing gastroplasty procedures. Such laparoscopic gastroplasty procedures would lessen or avoid the morbidity associated with open surgical gastroplasty procedures. Further, it would be advantageous to perform gastroplasty procedures in a manner that reduced the possibility of staple disruption.
2. Description of Background Art
Surgical gastroplasty procedures are described in Mason (1982) Arch. Surg. 117:701-706; Willibanks (1986) Surg. 101:606-610; and Deitel et. al. (1986) 29:322-324. Willibanks (1986) illustrates the TA-90.TM. surgical stapling device manufactured by U.S. Surgical Corporation, as described above. A gastroplasty method employing a specialized clamp having an aperture to define the small diameter flow passage between the partitioned portions of the stomach is described in U.S. Pat. No. 4,803,985. A laparoscopic stapling device is described in U.S. Pat. No. 5,040,715, the full disclosure of which is incorporated herein by reference. U.S. Pat. No. 4,802,614 discloses a surgical stapling device with features similar to the model TA-90.TM. manufactured by U.S. Surgical Corporation.